The United States and Japan will step up their defence cooperation to deal with the threat from nuclear-armed North Korea as tensions in East Asia remain high, officials from the two allies said on Thursday.

Qld strategy to boost immunisation rates

Unvaccinated children in Queensland may be banned from child care centres in a bid to boost immunisation rates.

Queensland's Health Minister Lawrence Springborg says the government hasn't ruled out the measure as it prepares to introduce a major immunisation strategy.

NSW has already introduced legislation that excludes unvaccinated children from child care and if it's successful in increasing immunisation rates then Queensland may follow suit.

"We won't rule it out but we are evidence based," Mr Springborg told AAP.

"We want to see what happens in NSW."

Mr Springborg says Queensland's immunisation strategy, to be launched by June, will aim to lift vaccination rates from about 91 per cent to 95 per cent.

"The people who aren't immunising their children are, quite frankly, getting the benefit from the people who are," he said.

Although Queensland's immunisation rates are about one per cent above the national average, Mr Springborg says the number of cases of measles, mumps, rubella and whooping cough emerging in the state are of great concern.

Since September there have been 50 confirmed measles cases in Queensland.

"It's worrying how we have measles popping up in the community again, which should be a thing of the past," Mr Springborg said.

"Measles can be a serious illness - it can lead to long-term disablement or death."

The LNP government only last week rejected an Opposition bill that would have allowed child-care providers to ban children whose parents couldn't prove they'd been vaccinated.

But Mr Springborg says any ban must be a uniform one that doesn't allow centres to choose whether to accept unvaccinated children.

The immunisation strategy, at this stage, will mainly focus on increasing public awareness and education about the importance of vaccination, he said.